News tagged with lightning

(Phys.org) —The Sun may be playing a part in the generation of lightning strikes on Earth by temporarily 'bending' the Earth's magnetic field and allowing a shower of energetic particles to enter the upper ...

The adage "Everyone complains about the weather but nobody does anything about it," may one day be obsolete if researchers at the University of Central Florida's College of Optics & Photonics and the University ...

(Phys.org) —Researchers in China have captured, for the first time, an instance of ball lightning, on digital video along with spectrographs. The accidental capture, detailed by the team in a paper they've ...

(Phys.org) —Russian physicists Alex Gurevich and Anatoly Karashtin claim, in a paper published in the journal Physical Review Letters, they have found more evidence to support their idea that lightning is cau ...

(Phys.org) —A fireball that appeared over the Sri Lankan province of Polonnaruwa on December 29, 2012 was a meteorite containing algae fossils, according to a paper published in the Journal of Cosmology. A team ...

Only a few decades ago, scientists discovered the existence of "sprites" 30 to 55 miles above the surface of the Earth. They're offshoots of electric discharges caused by lightning storms, and a valuable window ...

(PhysOrg.com) -- An Australian scientist studying photographs of fireballs, UFO sightings and a report of a strange green light in the sky suggests some UFOs may be ball lightning caused by fireball meteors.

(PhysOrg.com) -- Japanese farming folklore has it that lightning makes mushrooms multiply, and new research supports the idea. Mushrooms form a staple part of the diet in Japan, and the fungi are in such high ...

(PhysOrg.com) -- A 200-year-old report by a sea captain and a stunning photograph of the 2008 eruption of Mount Chaiten are helping scientists at the University of Illinois better understand strong volcanic ...

Lightning

Lightning is an atmospheric discharge of electricity accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. In the atmospheric electrical discharge, a leader of a bolt of lightning can travel at speeds of 60,000 m/s (130,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse silica sand into glass channels known as fulgurites which are normally hollow and can extend some distance into the ground. There are some 16 million lightning storms in the world every year.

Lightning can also occur within the ash clouds from volcanic eruptions, or can be caused by violent forest fires which generate sufficient dust to create a static charge.

How lightning initially forms is still a matter of debate: Scientists have studied root causes ranging from atmospheric perturbations (wind, humidity, friction, and atmospheric pressure) to the impact of solar wind and accumulation of charged solar particles. Ice inside a cloud is thought to be a key element in lightning development, and may cause a forcible separation of positive and negative charges within the cloud, thus assisting in the formation of lightning.